The customer observed that Page Builder blocks are not properly displayed on Windows browsers (see attached current.png).

Steps to reproduce:
1. Create a fresh installation of eZ Platform 3.1.2.
2. Go to BO and open the default preview of the main Landing Page.
3. Go to edit view.

Result:
Blocks are displayed in one column instead of two like expected (see expected.png image).

Note:
On some screens, there is a need to trigger the browser console to observe the wrong behavior.